Articular cartilage lines the ends of bones and facilitates frictionless movement of joints. Damage to the cartilage caused by injury or disease does not heal and the pathological changes resulting from this damage can be a source of great pain; limiting mobility and having a significant detrimental impact on the quality of life. Over time, lesions are likely to degenerate into osteoarthritis. Injury is not the only cause of osteoarthritis, with genetics, obesity, joint biomechanics, diet and age all playing a role.
Known surgical techniques for treating damaged cartilage comprise lavage and debridement (joint is flushed with fluid and damaged tissue removed providing temporary symptom relief); microfracture (penetration of the subchondral bone to stimulate bleeding in to the cartilage lesion in an effort to promote a fibrocartilage healing response); periosteal grafts (autologous periosteum is grafted into the defect site and sutured or glued into place); mosaicplasty (plugs of cartilage and bone are harvested from low weight bearing regions of the joint and transplanted into the defect); and autologous chondrocyte implantation (ACI) (cells are isolated and expanded from a cartilage biopsy from a non-weight bearing location, and the cells are re-introduced into the defect in a second procedure approximately six weeks later either in suspension or on a scaffold (Matrix-guided ACI-MACI)).